The Marvel Cinematic Universe has done a lot of things right since Iron Man kickstarted it in 2008 - from its fan-pleasing casting of iconic superheros, to its ongoing efforts to diversify its output - but with a few notable exceptions, it drops the ball all too often when it comes to the villains.
It started off on the right foot in this regard as Tony Stark's nemesis Obadiah Stane proved a worthy adversary, but it wasn't until Thor introduced Loki and The Avengers flesh him out that the MCU had an antagonist worthy of the famous Marvel brand.
Since he took on Earth's Mightiest Heroes in 2012, it's mostly been downhill for the MCU on the bad guy front. Sure, there are exceptions, like Vulture and Hela, but on the whole, villains remains an area where Marvel must improve.
Constant failings in this area have put the studio under pressure in the run-up to Avengers: Infinity War. Marvel has to get Thanos right, or 10 years of universe building could topple under his weight. And these are the mistakes it must learn from...